I received it too. I wonder if they sent this to all pro/max subscribers or only those who they’ve flagged as having used a third party harness.

I have a few accounts but have been avoiding OpenCode with my Pro/Max accounts because I had heard some were being banned. Have only been using Anthropic models through OpenRouter, but it ends up being cost prohibitive for anything reasonably complex. But, I haven't received emails in either account around the change. Anthropic probably figures that it's less ideal to draw attention to it if a user isn't using it in that way. Personally I'm not a fan of what they're doing and will likely drop them and go out of my way to find a different option and move away from their lock-in strategy. They're really no different than OpenAI at this point (for the worst).

FWIW: I did not receive it, and have never used my subscription outside of first party Claude tools. I was, however, able to claim the extra usage credit.

Interestingly, it looks like I haven't received a non-receipt email from them since August 2025.

I'm a pro subscriber and didn't get this so I wager its accounts they detect because i only use it in the browser and haven't seen this.